Guppy
Guppy is Isaac's Pet cat. Guppy is Mentioned in Isaac's Death Note. Well, the cat's out of the bag: Collecting the dead cat, Guppy's tail and Guppy's head OR Guppy's paw turns you into guppy, who can fly and spawns attackflies while attacking. It can be assumed that Guppy is dead by the time Isaac explores the world under the trapdoor, since you can find pieces of his throughout the adventure. Eventually you can also find the item Dead Cat which represents Guppy himself. Related items All items related to Guppy, except for Guppy's Hairball are Devil Room items. 'Guppy's Hairball' Loosely follows behind Isaac. Can be swung like a flail by rapidly spinning Isaac in a circle. Deals damage when it collides with enemy units. If an enemy unit is killed by the ball it increases in size up to a maximum limit. The larger the ball becomes the easier it is to swing, the larger its collision circle becomes, and the higher its damage becomes. Size is reduced at the start of each floor. Unlocked by transforming your Character into a Cat. Achieved by collecting 3 Guppy items in one playthrough (any combination of Guppy's Tail, Dead Cat, Guppy's Head, and Guppy's Paw). 'Guppy's tail' What might be guppys tail (couldn't get because he had 1 heart.) Guppys Tail is an item with the deal with the devil that cost one heart. What this does is it gives the ability to spawn more locked (gold) chests. If you have lots of keys this would be a good/smart thing to use them on. A great example of this item usage is in a challange run that doesn't have any secret rooms and is lacking librarys. 'Guppy's head' Spawns 2-4 Blue Flies to damage enemies. Flies won't spawn if entering a door while using it.Found in Devil Room for 2 hearts, the Curse Room, Challenge Room or as a drop from fight with The Fallen. 'Guppy's paw' Turns one Heart Container into 3 Soul Hearts.Does nothing for ???.Found in Curse Rooms, Devil Rooms and from bosses .Can be used indefinitely provided there is at least one heart container left. 'Dead Cat (Guppy)' Your HP is set to 1. You are followed by a floating cat head and have 9 lives (these still count as deaths on the statistics screen). You can increase your max HP as normal, but after each death it will reset to 1 again. (1 soul heart with ???) Even if you have more than three heart containers, you will only have one heart container left once you purchase Guppy, since it sets your HP to 1 immediately, not after your first death. If you buy him for the price of 2 hearts from the devil and you have 2 or fewer hearts, you will acquire him, die, and respawn with 1 heart (therefore losing 1 of the extra lives). The cost of purchasing items in the Devil Room must be met, but if it would kill you, you will respawn. Bug/Exploit: After defeating a boss, if you die after the item appears but before the boss disappears you will be able to fight the boss a second time for yet another item.'(Pick up the item, then kill yourself with a bomb or something similar. You will then respawn outside the boss room with one less life on your counter. Going back inside the boss room allows you to now fight the boss again for another item. Can be done as long as you have additional lives on your counter. Can also be performed after picking up a 1UP.) Guppy will sometimes appear as a collectable item as well as in the Devil room. Collecting more than one Guppy will not add any more lives if the player already has 9, but will reset your health back to 1. When you get additional heart containers your heart containers will reset to 1 after your first death.